Concrete is a well known building material that has been used for many years. In most cases a footing or foundation excavation is made and temporary forms of re-usable panels are joined together forming a void into which concrete in its plastic state is placed. Some finishing and/or vibration to remove air pockets and make the exterior surfaces of the concrete smooth is performed before the concrete sets up or hardens. Commonly, steel rods are placed in the void space prior to casting the concrete for additional strength. Types, materials, techniques of use, and actual use of the strengthening steel rods and other such inserts and artifacts through foundations, walls, floors, and roofs are well known in the building arts and are only inferentially discussed herein. The forms are removed when the concrete is hard, and additional structures on top of the concrete foundation wall are built when the concrete is strong enough. Long walls are cast in sections, and the forms are stripped and used for the other sections thereby minimizing the number of forms used. Joints between adjacent sections are made water tight by use of membranes cast into the cold joint between wall sections.
The "foundation" of a building may include a wall, usually beneath the ground level with footing directly under the wall, and a slab adjacent to and/or integral with the footing. Other variations exist as known in the art. Hereinafter, foundation and/or footing refers to such a "foundation." Typically, after the foundation or footing is cast, the foundation forms are removed and temporary wall forms may be erected on top of the foundation. Usually, the strengthening rods extend out of the top surface of the footing so as to be included when the wall concrete is placed. This techniques binds the wall to the footing making a strong joint between the two. After all sections of the concrete wall have been cast and the concrete is hard and strong enough, the wall forms are removed and temporary floor and column forms are erected spanning the distance between the various walls. Shoring supports the forms and the concrete floor slab. The floor forms and shoring are again removed, and the wall forms erected on the hardened floor slab for the succeeding levels. The steps are repeated until the concrete frame of the building is completed.
The process just described for casting concrete structures has many advantages, but some issues remain. For example, since the concrete must sufficiently harden before the next wall section or stage can begin, there is a substantial time delay, normally requiring a week or more between wall sections, floor/roof slab placement on walls, or vertical concrete structures cast on slabs; even though steel rods traverse the horizontal and vertical joints that interface one concrete section to another, the joints exist. The forms must be treated, erected, tied together and braced, and then disassembled after casting and cleaned for each individual concrete placement, concrete joints and interfaces must be sealed and made water tight, the outside and inside surfaces of the concrete often must be insulated, sealed, protected and finished with other materials for esthetic and/or practical reasons, and skilled labor and specialized equipment is often necessary to complete each stage of finishing a concrete structure. The result is that such construction is labor intensive, time consuming and costly.
Thomas Edison, in the early part of this century designed and patented a method for casting a monolithic concrete structure in situ. Several houses were made and remain standing today. The described Edison processes had many limitations. One was that the molds weighed hundreds of tons and were cumbersome, unwieldy, difficult to erect and bolt together. These iron forms presented a significant problem for transporting, assembling and disassembling. Heavy trucks and cranes were necessary to handle the molds.
It is an object of the present invention to provide a method and apparatus for molding, casting and encasing monolithic concrete structures in situ that is both practical and economical.
It is also an object of the present invention to provide a monolithic concrete structure with substantially no cold joints between concrete footings, walls, floors and roofs.
It is another object of the present invention to provide a complete molded or cast concrete structure where the mold is light weight, easily handled and remains in place permanently, such that there is substantially no finishing work necessary for either the interior or the exterior surfaces of the concrete face after the casting operation is completed.
It is yet another object of the present invention to allow a mold for a structure to be self supporting without temporary bracing or shoring and erected in situ, and wherein concrete can be placed into said erected molds substantially continuously. Another object of the present invention is to provide a means for removably connecting adjacent mold panels and components in an interlocking fashion.
Yet another object of the present invention is to provide a water tight, insulated, molded monolithic concrete structure where both interior and exterior faces of the completed concrete walls, and ceilings beneath floor and roof slabs are finished when the casting operation is complete.
Another object of the present invention is to reduce the need for skilled labor, specialized equipment and material storage at the construction site.
Still another object of the present invention is to provide pre-installed utility service lines and outlets in the mold panels prior to erection of the mold at the building site.
Another object of the present invention is to reduce the cost and the time to construct in situ concrete structures.